Squidtastic Voyage/That's No Lady - S4-E15
Corrected entry: In the one where Squidward inhales his reed and clarinet, when Spongebob and Patrick are in the lab guarding the submarine, neither of them has a helmet on.
The Lost Mattress/Krabs vs. Plankton - S4-E2
Corrected entry: Mr. Krabs claims he never heard of a bank. But in 3-19 "Krabby Land," he says "Hi, kids. Uncle Krabs has to go to the bank now." He also has a sack of money, proving that he does put his money in a bank, rather than a mattress.
Correction: Mr. Krabs never claimed he didn't know what a bank was - he just fell into a "cash coma". And the sack of money he had was taken by the children. And.I think I've read in the book "Spongebob Revealed" (this is not a direct quote) is that Mr. Krabs alternates his money from a bank to his mattress. Another thing.Squidward said in "Plankton's Army" that he kept the secret formula in his mattress too. Supposing Sheldon were to open the mattress he could never have found the secret formula in the mattress with all his money inside.
Correction: That's because the lab is outside the dome. There wouldn't be any point in wearing a water helmet if they were outside of the dome because they would already be breathing water.
Casual Person